I suggested to JavLibrary that they add this genre as a searchable category. They said they might think about it if I give them a large list of applicable titles, so I'm working on that now. Hopefully when I submit the list, they keep their word.
Absolutely love this genre, and I love how many hot, young JAV girls do such a great job of acting passionate and horny when they do the scenes (or perhaps some of them aren't acting at all).
GVG definitely has the most good titles for this by far, but NSPS might have the best overall. In NSPS movies, the girls seem extra turned on and make love passionately.
Check out NSPS-581:
From what I can tell (I don't know Japanese), a hot young wife works at a small store with an old man as her coworker. She comes home to her drunk, useless slob of a husband everyday and it's so unsatisfying.
One day, as the girl and the old man are stocking shelves in the back with nobody around, he jumps on her and starts forcing a kiss. She's so horny and turned on, she barely fights it, quickly accepting and enjoying his tongue in her mouth. They make passionately love right then and there and then several times after that, as well.